Hitherto in an automotive vehicle fuel system piping such as a feed tube, a return tube, an evaporation hose, a filler hose and the like, a piping structure which is formed of metal, rubber, resin or a mixture of two or three kinds of these has been used. Particularly recently, one formed of metal and having hitherto served as the mainstream is being replaced with one formed of resin from the viewpoints of no rust being produced, weight-lightening being possible, and being advantageous in cost.
Japanese Patent Provisional Publication No. 5-164273, Japanese Provisional Publication No. 11-156970, Japanese Patent Provisional Publication No. 10-230556, Japanese Patent Provisional Publication No. 10-30764 and Japanese Patent Provisional Publication No. 2000-55248 disclose relating arts.